NetworkManager static routes not applied

The interface has VLAN enabled. on default vlan (management lan, 10.0.0.1/24 physical if "enp0s31f6") I set

ipv4.routes: { ip = 192.168.0.1/32, nh = 10.0.0.1 }; { ip = 192.168.1.1/32, nh = 10.0.0.1 }

This traffic is allowed by 10.0.0.1.

route shows

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         gateway.mynet   0.0.0.0         UG    400    0        0 Private
10.0.0.0        0.0.0.0         255.255.255.0   U     100    0        0 enp0s31f6
10.1.0.0        0.0.0.0         255.255.255.0   U     400    0        0 Private
link-local      0.0.0.0         255.255.0.0     U     1000   0        0 enp0s31f6
172.17.0.0      0.0.0.0         255.255.0.0     U     0      0        0 docker0

When I add those entries manually using

sudo route add 192.168.0.1 gw 10.0.0.1
sudo route add 192.168.1.1 gw 10.0.0.1

route shows

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         gateway.heimnet 0.0.0.0         UG    400    0        0 Private
10.0.0.0        0.0.0.0         255.255.255.0   U     100    0        0 enp0s31f6
10.1.0.0        0.0.0.0         255.255.255.0   U     400    0        0 Private
link-local      0.0.0.0         255.255.0.0     U     1000   0        0 enp0s31f6
172.17.0.0      0.0.0.0         255.255.0.0     U     0      0        0 docker0
192.168.0.1     10.0.0.1        255.255.255.255 UGH   0      0        0 enp0s31f6
192.168.1.1     10.0.0.1        255.255.255.255 UGH   0      0        0 enp0s31f6

NetworkManager does not apply those static routes.

• They show up correctly in nmcli
• They show up correctly in nmtui (I prefer to use this)
• They show up correctly in ElementaryOS network settings

Where is my mistake?

Or is this a bug? I found reports online but they were closed with "WONT FIX" and they're old.

Thanks for help